The present invention is directed to antitheft devices for bicycles and, more particularly, to an efficient antitheft control device that can be used with a normal lightweight battery.
Bicycle antitheft devices take many different forms. The simplest antitheft device is a lock that physically secures the bicycle to a stationary object such as a fence. More elaborate bicycle antitheft devices use electronic circuits to control a lock. For example, JP 8-260784 shows an antitheft device that may be operated either manually using a key or electronically using a transmitter. Antitheft control devices that operate electronically are often also used in automobiles and are very convenient because the user can operate the antitheft control device by merely pressing a button on a key or key holder to transmit a lock or unlock command signal to the antitheft control device. The antitheft control device then locks or unlocks the antitheft device (e.g., the locks on the automobile door) in response to the command signal
In order to receive the lock or unlock command signal at any time, the command signal receiver in the antitheft control device must be powered at all times. This does not pose a problem with automobiles because automobiles use rather large batteries that are regularly recharged during operation of the automobile. However, such batteries are not used on bicycles because of the size and weight of the batteries. Electronic devices used with bicycles, such as bicycle computers and automatic transmission devices, must use small batteries that are as lightweight as possible. Such batteries are usually not rechargeable. Thus, so far a remote-controlled bicycle antitheft device would not be practical because a constantly powered signal receiver would quickly discharge the battery.